Tractor.



LM. 6; H, E. JOHNSON.

TRACTOR.

APPLICATION FILED JULY 19, 1913.

Lm'fi figg. Patented Feb. 9, 1915.

IN V EN'LOR 5.

JOHN M. JOHNSON AND HENRY'E. JOHNSON, OE WINTERS, CKLTEO'RNIA- TRACTOR.

Specification of Letters Patent.

Patented Feb. 9, 1915.

' Application filed July 19, 191a Serial no. veaoaa To all whom it may concern Be it known that we, JOHN M. JOHNSON and HENRY E. J OHNSON,l)Otl1- citizens of the- United States,residing at WVinters, in the county of Yolo and State of California, have invented new and useful Improvements in Tractors,

is a specification.

This invention relates to traction engines,

and particularly to a tractor having means rendering it particularly useful for work in orchards, vineyards and under other conditions where it is desirable or necessary that the machine' should .be able to make short turns.

It is the object of the present invention to provide a tractor having means automatically, operative for the application of re sistance to the inside of either of the traction wheels. at a predetermined time when making a turn, and further to provide means whereby a braking force can be applied to either of the wheels independently, or to both simultaneously .with equal or different pressures.

A further object of the present invention is to provide in combination'witha tractor, a driving mechanism including a driveshaft with a diflerential gear, and means for applying a braking force to either of the driven wheels, said means being automatically operative after a predetermined amount of movement of the steering wheel of the tractor has taken place. I

The present invention consists in the combination in. a tractor, having a steering wheel or mechanism and a driving shaft provided for differential movement, of means operable and controlled by the steering mechanism for applying a braking resistance to the inside turning wheel when making turns in either direction; and further consists in the provision of manuallyoperable devices whereby said braking mechanism can be applied, safely and independently of the operation of the steering mechanism.

The invention consists of the parts and the combination and construction of parts as hereinafter more fully described and claimed, having reference to the accompanying drawings, in which- Figure 1 is a side elevation of the improved tractor, partl broken away to show the brake mechanism on one side. Fig. 2 is a plan view of the tractor, showing the braking mechanism in detail.

of which the following In the drawings 2 represents a suitable form of frame or. chassis for the tractor,

which is supported at its forward end upon,

an appropriate type of steering' wheel 8,

having a horizontally disposed turnabletable 4E towhich is connectedoperating links or connections 5, one on: each side, and which are extended rearwardly and joined,

as at 6, toa chain or other operating con- RGGtlOH 7., and engaging and. being operable by a sprocket or suitable driver 8, here shown as secured on a, hand-wheel shaft 9,

turnable by a handswheel- 10, at the top. The rear end of thetractor is supported by a pair of traction wheels 11-, on a transverse a de 12; the tractionwheels ll being providedeach wlth a gear 13; thesegears beingrespectively engaged and. driven by pinions 14 which are secured on the outer ends of a two-part drive shaft 15 which forms a.

portion of the (inferential mechanism, indicated generally at 16, to which power is transmitted by a transmission gear, indi-v cated at17. The; transmission gear derives power from a driving shaft 18,. which may be connected by a clutch 19, to a suitable motor 20 on the. chassis,

The short turning of this machine is aided by the use of a; suitable type of brake-clutchesqor brakes 21, which may beapplied to brake-wheels 22, fast on the sections of the drive shaft. 15. The brakes 21 are adapted to be operated by divers means, which partly consist, of levers 23 secured to rocker shafts 2,4, to which are connected the free ends 25 of the brakes 21. The brakeoperating levers 23, of which there is one for each of the traction Wheels 11, are extended downwardly and connected to the adjacent tension members of the steering connections 5; in the present. instance the levers 25 being shown as connected by a yieldable, flexible means including a spring 26 secured at one end to its adjacent lever 23and attached at the other endto a piece of chain or other suitable connection 27 which is attached in the present case to the joint 6 of the chain 7.

Preferably the connections 2627, which join the levers 23. to the steering connection 7, are normally sufliciently slack to permit the turningmovement of the steering wheel 3, when the hand-wheel 10 is operated a predetermined amount of movement either side of its normal center line, without drawing the connections 2(r27 toward it; thus enabling the tractor to turn in circles of large radius freely. After the hand-wheels have been turned sufliciently then the tension members 57 on one side will, as it moves rearwardly, draw the lever connections 26-27 taut, and thus rock the lever 23' and its'rocker-shaft 24, to apply the brake 21 to the brake-wheel 22; the flexible part 26 of the connection affording a safety against excessive strains and causing the brake band 21 to be applied gradually during its application.

Since there is one of the brake mechanisms on each side of the differential gear 16, and the lever 23 of each of the brake mechanisms being respectively connected'to that portion ance ofi'ered to the differential gear by the checking action" of the brake on its respective section of \shaft 15, and causing the power to be transferred to that traction wheel which is on the outside of the curve in which the tractoris swinging.

As it may be desirable to apply the friction brakes when the vehicle is on the downgrade, and also in case one of the wheels strikes a soft or smooth place and should slip, there is provided and connected to each of the brake-applying levers 23 .a link 28, to one end of which is connected a handlever 29, which, when operated, actuates its respective lever 23 to apply'its brake 21. As there is one of the hand-levers 29 on each side of the tractor for'applying the brakes 21,'it is manifest that the traction wheels 11 can be independently controlled by the-application of its respective brake 21, and also in case of necessity both of the hand-levers 29 can be simultaneously operated so as to apply both the brakes at once.

, Thus we have provided a tractor for all purposes and especially contrived-to work in an orchard and among trees or any place where it is desirable that the machine should be able to turn short. The short turnin of this machine is aided by the use of two riction clutches or brake clutches, one on either side of the difierential, which are made to Work automatically with the tiller wheel. These clutches can be so adjusted that they will not come into play until the tiller wheel is turned to any. desirable angle to either side of its central position, therefore having no effect when the tractor is turning in a large radius. These friction brakes or clutches are also connected with levers, one for each side, which can be used at will for increasing or decreasing the friction on either side independently or simultaneously. It is obvious that the brake levers can also be used for applying the brakes to the drive wheels when going down grade, and also in case one wheel strikes a soft or smooth place and should slip, friction can be applied to this wheel and thus aid the other drive wheel in pulling out of the diflicult place.

The advantageof this method over the tractor with an independent clutch for eacn drive wheel and no differential is that the operator on the latter must, in turning, operate the tiller wheel and also'the clutch engaging with the inside drive wheel at the same time which requires considerable skill and attention, and the tractor with a diflerential and no friction brakes on either side cannot turn short enough for all purposes in loose soil, such as are encountered in all orchard work and cultivation in general on the farm.

Having thus described our invention what we claim and desire to secure by Letters Patent is:

1. In a tractor having steering means, and a pair. of drive wheels, a differential mechanism includinga tw0p.art drive shaft for operating said wheels, a brake mechanism for each of saidtwo parts of the drive shaft, a connection embodying a spring element extending from each brake mechanism to said steering means, and means whereby the brake mechanisms may be separately operated independently of the steering means.

2. In a tractor having a pair of drivers and a steering mechanism, means for retar-ding each driver, and spring means for- In testimony whereof we have hereunto set our hands in the presence of two subscribing witnesses.

JOHN M. JOHNSON.

. HENRY E. JOHNSON.

Witnesses:

R. L. NIEMANN, R. 0. Games. 

